/**

    Let inheritance help with memory efficiency

*/

function SignalFire(ID, startingLogs){

    this.fireID = ID;

    this.logsLeft = startingLogs;

}

SignalFire.prototype = {

    addLogs: function(numLogs){

        this.logsLeft += numLogs;

    }

    lightFire: function(){

        alert("Whooosh!");

    }

    smokeSignal: function(message){

        if(this.logsLeft < this.message.length / 10){

            alert("Not enough");

        }else{

            this.lightFire();

            var x = this.message.length;

            for(var i = 0; i < x; i++){

                alert("((("+this.message[i]+")))");

                if(i % 10 == 0 && i != 0){

                    this.logsLeft--;

                }

            }

        }

    }

}

var fireOne = new SignalFire(1, 20);

var fireTwo = new SignalFire(2, 18);

var fireThree = new SignalFire(3, 14);

fireOne.addLogs(8);

fireTwo.addLogs(10);

fireThree.addLogs(14);

fireThree.smokeSignal("Goblins!");

//The addLogs method is found in one useful place, instead of being

//replicated across all signalFires.

/**

    Adding individual dom elements ain't always speedy

*/

//

//**BAD**

//

var list = document.getElementById("kotwList");

var kotw = ["Jenna Rangespike",

            "Neric Farthing",

            "Darkin Stonefield"];

for(var i = 0, x = kotw.length; i < x; i++){

    var element = document.creatElement('li');

    element.appendChild(document.createTextNode(kotw[i]));

    list.appendChild(element);

}

//appendChild(); function each time this list is appened, we access the DOM

//and cause an entire document reflow. Not as speedy as we'd like, especially

//if we list was huge...

/*

    Improve: Use a document fragment to insert additions all at once

*/

var list = document.getElementById("kotwList");

var kotw = ["Jenna Rangespike",

            "Neric Farthing",

            "Darkin Stonefield"];

var fragment = document.createDocumentFragment();

for(var i = 0, x = kotw.length; i < x; i++){

    var element = document.creatElement('li');

    element.appendChild(document.createTextNode(kotw[i]));

    fragment.appendChild(element);

}

list.appendChild(fragment);

/*

    Improve: declare variables as few times as possible

*/

//

//**GOOD**

//

var list         = document.getElementById("kotwList"),

    kotw         = ["Jenna Rangespike",

                    "Neric Farthing",

                    "Darkin Stonefield"],

    fragment     = document.createDocumentFragment(),

    element;

for(var i = 0, x = kotw.length; i < x; i++){

    element = document.creatElement('li');

    element.appendChild(document.createTextNode(kotw[i]));

    fragment.appendChild(element);

}

list.appendChild(fragment);

/**

    Efficient choices for string concatenation

*/

//

//**OK**

//

var knight = "Jenna Rangespike",

    action = " strikes the dragon with a ",

    weapon = "Halberd",

    turn = "";

turn += knight;

turn += action;

turn += weapon;

//It is ok because the code is short and clear

//

//**NOT GOOD ENOGUTH

//

var newPageBuild = ["<!DOCTYPE html>", "<html>", "<body>", "<h1>",

                    *** a hundred or more other html elements***,

                    "</script>", "</body>", "</html>"],

     page = "";

for(var i = 0, x = newPageBuild.length; i < x; i++){

    page += newPageBuild[i];

}

//

//**GOOD**

//

page = newPageBuild.join("\n");

//Using join is much faster than using '+=' and looks simple and clear!!

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